[raylad]

The existing PrEP drugs work differently.

Cabotegravir is an integrase strand transfer inhibitor. This means it blocks the HIV's enzyme integrase, thereby preventing its genome from being integrated into the human cells' DNA.

Emtricitabine is an analogue of cytidine. The drug works by inhibiting reverse transcriptase, the enzyme that copies HIV RNA into new viral DNA.

Both of these drugs actually prevent infection.